Antimanipulative combination lock



Oct. 16, 1956 c. M. HIRN ANTIMANIPULATIVE COMBINATION LOCK Original Filed April 23, 1952 INVENTOR. ('/Mrles /w nited States PatentO AN TIMANIPULATIVE COMBINATION LOCK Charles M. Hirn, Cincinnati, Ohio, assignor to The Mosler Lock Company, Covington, Ky.

Original application April 23, 1952, Serial No. 283,901. Divided and this application November 10, 1955, Serial No. 546,141 f Claims. (Cl. 70-322) The familiar known and used combination locks of several types and numerous makes are allegedly insecure against surreptitious opening by certain skilled persons who, in the absence of a knowledge of the combination by means of which the lock is to be opened, reputedly form the combination in a given lock with only the aid of the sound and feel of the mechanism while operating the usual dial knob of the lock.

Itis the major object of the present invention to render the aforesaid lock structures anti-manipulative by such alleged persons and practices without expensive or elaborate redesigning of the existing lock structures.

This application is a division of my copending United States patent application Serial No. 283,901, tiled April 23, 1952.

A further object of the invention is to accomplish the aforesaid purpose essentially by a mere reversal of the spring member of the lock which operates on the fence so that the latter is constantly urged away from the notched tumbler series of the lock and to provide simple and inexpensive arrangement of the lock parts which make it impossible to maintain a manual control of the tumblers and the lock operating cam in such a simultaneous manner as would aiord an intelligible external sound or feel that could indicate the position of the tumbler notches interiorly of the lock.

Another object of the invention is to provide in the various types of combination locks a simple arrangement of the existing parts wherein the bolt or slide is constantly biased to locking position and the fence means isconstantly urged out of contact with the tumblers.

These and other important objects are attained by the means described herein and exemplied in the accompanying drawings in which:

Fig. l is a fragmental elevational view of a door having a combination lock embodying the invention operatively mounted thereon, the cover and tumbler assembly being removed to disclose the interior of the lock casing with its associated parts in a normally locked position.

Fig. 2 is a vertical center sectional view through the door and the fully assembled lock, looking in the direction of the arrows 2--2 of Fig. l, the tumbler series being shown partly in dashed lines and partly broken away, and the dial knob, arbor and driver being shown in full lines in the tumbler actuating position, and also in dotted lines in the bolt actuating position wherein the driver is inoperative on said tumblers.

Fig. 3 is a fragmental view of the structure of Fig. 1 with the parts in position retracting the lock bolt.

Fig. 4 is a cross sectional view taken on line 4 4 of Fig. 3.

Fig. 5 is a perspective View of a fence member forming a detail of the lock.

It has been proposed to remedy the alleged insecurity of conventional combination locks by the use of attachments that extend through, the lock casing to the exterior- 2,766,609 Patented Oct. 16, 1956 fice thereof but such arrangements leave much to be desired because locks so constructed may be required to be mounted on structures where space is too limited or Where the attachment may be subject to surreptitious tampering while the structure is unlocked and open.

By the means of the present invention these and other objections are avoided, and compact and eicient antimanipulative locks are provided.

ln order that the simplicity and low cost of producing the improved antimanipulative locks of the present invention may be more readily understood, it should be observed that most of the parts of the corresponding type of prior known familiar lock may be adapted and utilized unchanged in the improved lock while simple and inexpensive changes are made in the remaining few parts. It is thus possible to convert existing old locks in stock or in use in a minimum of time and with a minimum of modified parts if desired.

Reference is now made to a familiar type of lock embodying the antimanipulative feature of the present invention and illustrated in Figs. 1-5 of the drawing. A door 10 or the like, to be controlled by the lock, has mounted on its rear face a lock casing 11, secured by screws 12 in known manner. The casing has xed thereto a tube or barrel 13 which extends through a bore in the door slightly beyond the outer face and is there arranged in known manner to secure a dial ring 14 tightly against the front face of the door.

Supported for rotation in the tube 13 is the usual dial stem or arbor 15 having an exterior operating knob 16 and dial 17, the latter adapted to turn in a recess in the dial ring 14 on the door. Within the casing 11 a driver and cam disc 18 is arranged in axially adjusted relation on stem 15 to accommodate the thickness of door 10 and in this instance to afford a predetermined axial shifting ofthe stem 15 in the tube 13 and a corresponding shifting of the driver 18, which axial shifting distance is, in the lock to provide means whereby the dial stem 15 may be yieldably urged to assume axially shifted positions at opposite limits of reciprocation, or at least one of such limits. As shown herein the stem member 15 has a pair of spaced annular grooves 20 and an intervening annular bead 21, while a leaf spring 22 seats in an external longitudinal groove 23 in tube 13 and has one end 24 securedl to said tube. The opposite downturned end 25 of the spring passes through an aperture in the tube wall and is raised by bead 21 as stem 15 is reciprocated so that said pawl end 2S of the spring entering one of the grooves 20 yieldably resists accidental longitudinal movement of the stem and its dial and knob.

The cover 250, which is removably attached in known manner to casing 11 has mounted thereon a coaxially arranged series of rotatable notched tumbler discs 270 which is coaxial with and operable by the driver 18 (see Fig. 2) these parts being adapted unchanged from a corresponding type of prior known lock and a detailed description thereof is omitted because the structure and operation are entirely familiar to those versed in the art. Each disc of the series 270 has a lug 2700 which may be mounted for limited rotary lost motion with respect to the axis of the disc. On the rear face of one disc is a pin 27000 that will engage the lug 2700 of an adjacent disc whereby the latter has rotary movement imparted to it for aligning the peripheral notches according to combination.

From the foregoing it will be seen that when the dial stem and driver disc are adjusted to the position shown in full linesin Fig. 2, the driver lug 19 will cooperate with the adjacent member of the tumbler disc series 276 and that rotation of the dial and knob according to predetermined combination will serve to set up the tumbler discs with their notches (not shown) in alignment in known fashion to permit further operation of the lock for opening the same. However when the dial knob and its stem are pulled out to the dotted line position shown in Fig. 2, the driver i8 carries the driver lug 19 out of operative connection with the tumbler discs 270 and rotary movement of the dial knob does not affect the tumbler setting.

A slide plate 26, which may be identical in form with that used in the prior known locks of corresponding type, is mounted in known manner for reciprocation in the casing 11 and has the usualbolt member 27 formed integral therewith and guidedly movable into and out of the said casing through an opening in the side wall of the casing. The slide 26 has the customary cam slot 28 therein. A fence member 29 is pivoted in known manner on a fixed pin 30 in the casing 11 and has a depending lug 31 which extends into cam slot 2S in plate 26 so that reciprocation of the plate eiects hinged movement of the fence member and vice versa. The free upright edge 32 of the fence member is adapted to enter the aligned notches in the tumblers 27 in well known manner. The fence member 29 of the present invention differs in structure, from the fence member of the prior known locks of corresponding general type, (see Fig. 2) in one simple feature, namely in the provision of a iixedly attached or integrally formed extension or finger 33 that is longitudinally curved on a common continuous arc with the fence (Figs. 1 and 3) and that projects from the free edge 32 of the fence at a point just above the lug 31. The said finger 33 will thus be disposed in a plane closely adjacent the face of slide 26. As will be readily seen in Fig. 4, the extension r nger is disposed in the plane which the driver 18 occupies when said driver disc is in its retracted position so that the driver cannot be retracted, by pulling the dial knob 16 to the dotted line position as shown in Fig. 2, until the peripheral cam notch 34 in the driver registers with extension finger 33 on the fence, due to the fact that said extension 33 always extends at least partially into the path of reciprocation of the driver disc 18.

It should now be observed that the fence spring 35 in the improved antimanipulative lock of the invention has been reversed so as to yieldably urge the fence in a direction such that the edge 32 of the fence is withheld from contact with the peripheries of the tumbler discs 270 which are in substantial registry withv the periphery ot driver disc 18. The action of spring 35 also serves to urge the slide Z6 and its bolt 27 to a locking position. The arrangement just described is exactly opposite to and contrary to that in the prior known combination locks commonly used for important security.

The lock of the invention makes it possible to connect the driver with the tumblers only when the said driver and the dial stem and knob are in the full line position in Fig. 2, at which time said driver 18 in an axially shifted position out of the path of the extension finger 33 on the fence. Hence it is impossible at such time to gain any intelligence, through the senses of hearing or feeling (or both), as to the momentary relation of any of the tumbler notches to edge 32 of the fence. If an attempt is now made to shift the driver disc 18 in an axialdirection the projection 33V will baiile such attempt unless the cam notch is in registry with said projection. VIf the said projection and notch are not in registry the rotary adjustment of the stem necessary to establish the condition of registry will effect a corresponding change inthe adjustment of one or several of the tumbler discs because the driver lug 19 remains operatively connected with the adjacent tumbler disc until the condition` of registry is established between extension 33 and the driver notch 34. Assuming now that the dial knob has been turned to posiknob has been pulled out to cause the notch to receive said extension therein, manual rotation of the knob will begin to rotate the driver and its cam notch 34 and the latter will engage the extension and begin to move the fence against the resistance of the fence spring. 'Ihis will yield a uniform predominant mechanical sound and sense of feel that yields no intelligence of the condition of the lock to the operator. It the rotary movement is conof the `spring 35.

tion, registering notch 34-Y with extension 33, andthat said 75 tinued the edge 32 of the fence approaches the peripheries of the tumbler discs and will' contact any and all tumbler discs which have not been adjusted with their respective tumbler notches in position to receive the fence. The existence .ofV the mechanical andL spring resistance present while such attempt is made to feel the condition of the tumblers predominates under these circumstances and eliminates the chances of employing any trained feel or touch sensitivity on the part of an operator.

In the present embodiment of the invention it should be observed that an appreciable degree of manual turning pressure must be exerted and constantly maintained on the dial knob in order to hold the fence at or near the peripheries of the tumbler discs against the resistance If such pressure is momentarily released the fence is shifted by its spring to the position shown in Fig. l and the slide 26 and its bolt are projected to the fullyl locked position as shown in said' Fig. l. During any such operations it is of course impossible to determine the positions of the tumbler notches or to impart any adjusting movement to the tumblers themselves.

It will be understood that the invention is not to be considered as limited to embodiment in the specic type of conventional locks indicated herein in order to render them antimanipulative. The disclosure is sutliciently representative of the simple and inexpensive adaptation thereof to other specific locks of these and other types to enable the application ofthe invention to the latter by those skilled in the art within the spirit of the invention and the scope of the appended claims.

It is to be noted special completely new designs of lock of antirnanipulative nature are not necessary, but are not to be excluded from the practice of the present invention.

What is claimed is:

l. In a lock of the class described the combination with a casing, a slide plate, with a cam slot adjacent one edge, reciprocable in the casing to and from locking position, and a cover on the casing supporting a plurality of rotary, peripherally notched tumblers with the lowermost tumbler spaced above the top of said plate, of a fence member pivoted adjacent said plate with its bottom edge in closely spaced parallelism above the top of said plate and its free end edge movable to and from the peripheries of said tumblers, an. integral lug on the bottom edge of the fence depending into said cam slot whereby the plate is moved toward unlocking position as thefree edge of the fence approaches the tumblers, an integral finger projecting outwardly from the free end edge of the fence and between the lowermost tumbler and the plate closely adjacent the latter, a spring biasing the fence to' a position with its free end edge away from the peripheries of the tumblers and urging the plate to locking position, a driver, of a thickness approximating that of said linger, with a lug on the top face and a cam notch in the periphery, interposed in the. space between said plate and lowermostv tumbler, and' an externally operable arbor fixed to and mounting the driver for rotary adjustment and axial shifting movement on a common axis with said tumblers, the end of the tinger being at all times inwardly of the periphery of the driver and withholding the driver from axial movement into the plane of said iinger when the cam notch is out of registry with said finger, the lug on the driver in the last named position being coactively related to the lowermost tumbler,

and the driver being shiftable by the` arbor from said position. to first render said driver lug inoperative on said tumbler and secondly to locate. said nger in the cam notch of the driver, whereby the said driver is then rotatable by the arbor to move the free end edge of the fence toward the tumblers and shift said plate toward unlocking position.

2. In a lock of the class described the combination with a casing, a slide plate reciprocable to and from locking position, and a cover supporting a series of rotary, peripherally notched tumblers with the lowermost tumbler in spaced parallel relation above said plate, the plate having a cam slot adjacent one edge, of a pivoted fence in the casing having a lug depending into said cam slot whereby the fence and plate are movable together in either direction, a spring urging the fence away from the tumblers and thereby urging the plate toward locking position, an externally operable arbor extending into the casing coaxially of the tumblers, a driver Xed on the arbor and interposed between the plate and the lowermost tumbler, said arbor being rotatable and axially shiftable to alternately shift the top face of said driver toward and away from the lowermost tumbler, said driver having a lug on the top face to operatively engage the lowermost tumbler when the driver is shifted away from the plate, and further provided with a peripheral cam notch, and a linger projecting from the free end edge of the fence in a plane below the driver when the latter is operatively engaged with said tumbler whereby the latter may be adjusted in known fashion to align the peripheral tumbler notches for receiving the free end edge of the fence, said driver being rotatable to register its cam notch with said linger to permit axial shifting of the driver from operative engagement with the tumbler into the plane of said finger to permit the driver to move the free end edge of the fence into the aligned cam notches and shift said plate out of locking position.

3. The combination as set forth in claim 2 characterized by the fact that the fence and its linger are longitudinally curved on a common continuous arc.

4. The combination as set forth in claim 3 characterized by the fact that the free ends of the fence and finger when out of engagement with the tumbler notches and cam notch, respectively, are disposed on one side of a plane containing the aXes of the arbor and the fence pivot and are moved through said plane to the opposite side of the latter as they are moved respectively into the aligned tumbler notches and the driver notch.

5. The combination as set forth in claim 2 characterized by the fact that the arbor is yieldably retained at the opposite limits of its axial movement.

No references cited. 

